Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
3;~:~
~ . .
.':
The present invention generally relate~ -to puhlic
works machines such as hydraulic loading shovels.
Known self-propelling hydraulic loading shovels
usually comprise a rigid chassis provided with four wheels,
at least twolof which are driving wheels and on which are
mounted one or two pairs of stabilizers. This chassis carries
a rotatable superstructure at one end of which is pivoted a
working attachment.
One drawback of these machines lies in the f;-ct that
they are not suitable for displacement over poor ground, due
to their small ground clearance and to the small trailing
angles resulting from the presence of the stabilizers. Simi-
larly, displacement on inclined ground in a direction perpen-
dicular to the slope of this ground is limited to small
inclinations, as the limit of lateral tip of the machine is
rapidly attained. In addition, it is impossible to dig a
vertical trench perpendicularly to the direction of the slope
; in view o the small clearance of the stabilizers or the wheels,
which does not enable the machine -to be placed in a horizontal
position.
According to another known construction~ the wheels
.,1
are mounted on pivoting arms and the machine comprises a base
provided with cross-pieces at its ends and on which it rests
during operation, the wheel-carrying arms being lifted. The
base comprises at its centre a gear ring for the orientation
of the whole superstructure, on which the wheel-carrying arms
are mounted, whilst the base rests on the ground. These wheel-
carrying arms are lowered for displacement but, despite the
improvement obtained, the presence of the stabilization cross-
-- 1 --
32~
'
pieces reduces the leading and tra:iling angles.
In order for example to be able to dig vertical trenches in adirection perpendicular to a slope, it has already been proposed to produce
a machine provided with a pair of wheels mounted on wheel-carrying arms
which may pivot on one end of a chassis and with a pair of stabilizers
provided at the other end of this chassis, the superstructure being rotat-
able on said chassis through a gear ring allowing orientation. The
differential control of the wheel-carrying arms and the stabili~ers makes
it possible to maintain the machine in a vertical position, perpendicularly
to the slope. However, such a machine cannot travel on a highway by itself.
It must be transported on a vehicle with a platform and it travels on the
site by abutting on the working attachment.
It is an object of the invention to remedy the drawbacks of
existing machines and to allow a self-propelling hydraulic loading shovel
to be produced which may tra~el both on the highway and on poor ground due
to its adjustable ground clearance, and further capable of working on ground
having a high angle of slope, in conditions making it possible, if desired,
to dig vertical trenches perpendicularly to the slope of the ground.
The present invention accordingly provides a vehicle comprising
a lower chassis, a first pair of wheels carried by said lower chassis near
one end of said chassis, a pair of liftable or retractable stabili~ers
carried near another end of said lower chassis, a superstructure adapted
; to carry working equipment, said superstructure being rotatably mounted on
said lower chassis, a second pair of wheels carried by said superstructure,
means for moving said second pair of wheels between a lifted position and a
position in contact with the ground when said superstructure occupies a
. position with respect to said lower chassis such that said second pair of
wheels carried by said superstructure is directed towards the end of the
machine opposite to that end carrying said first pair of wheels, and means
for controlling the rotation of said superstructure with respect to said
` D
.~
.
~6~
lower chassis when said second pair of ~heels is resting on the ground, for
operating the machine during its movement from one place to another.
The wheels provided on the lower chassis are advantageously ad-
justable relatively to this lower chassis in order to be able to vary the
ground clearance of the machine, and their adjustment stroke is such that
they may be brought into a lifted position in which the machine may rest on
the ground by its lower chassis.
At least one of the pairs of wheels of the lower chassis and of
the superstructure can be mounted on arms pivoting about horizontal axes,
and means may be provided for controlling said arms for adjusting or liEting
the wheels. According to an apparently advantageous arrangement, the
horizontal pivot axes of said arms are oriented transversely with respect
to the longitudinal axis of the machine.
According to a preferred embodiment, the stabilizers are mounted
on the opposite sides of the lower chassis so as to be able to pivot about
horizontal axes, and means such as hydraulic jacks are provided for ensuring
. ~
their displacement between a working position ~abutment on the ground) and
a lifted position. However, it will be understood that these stabilizers
could be provided on an end face of the lower chassis. These stabilizers
can also be mounted so as to be able to pivot about vertical axes, this
enabling their orientation with respect to the lower chassis to provide
an optimum stability adapted to the ground conditions encountered.
A suitable arrangement consists in providing the wheels of the
lower chassis towards one end thereof and the stabilizers
D
63~
towards the other end, in order to increase the stability
during operation.
The superstructure can be rotatably mounted on the
lower chassis by means of a gear ring, as known for this
type of machine, comprising a gear ring meshing with a pinion
or like member. According to another feature, means are pro-
vided for driving said pinion, and thus the gear ring,
selectively from a steering mechanism or from the steering wheel
of the machine, so that the steering of the machine during its
transport or displacement is ensured by articulation of the
lower chassis and the superstructure, each of which is resting
on the ground through a pair of wheels, about the axis of the
gear ring. However, it will be understood that these movements
of orientation or steering of the machine by articulation may
be obtained by other means~ for example by hydraulic jacks.
The propulsion of the machine may be ensured from one
;-~ or more hydraulic motors driving a mechanism kinematically
connected to at least one of the pairs of wheels~ preferably
to the wheels provided on the superstructure, for example by
a chain and pinion drive.
According to a possible arrangement, orientation of
` the superstructure may then be controlled from this mechanism,
or example through a disconnectable device. In such a case,
the pinion or like member meshing with the gear ring is also
connected through a disconnectable device to the steering
wheel of the machine. 'rhis connection may be effected by
hydraulic means comprising a small hydraulic steering motor~
In this case, a valve can be provided in the system to avoid
driving the steering wheel upon orientation of the superstruc-
' '
.,~
~E6~
ture during operation.
Acc~rding to another e~mbodiment, a devlce independent
of the system of propulsion of the machine is provided to
ensure both the orientation of the superstructure and the
steering of the machine9 a disconnectable means or a system
of hydraulic valves being provided to connect this device
functionally to a source of energy~ such as the hydraullc
system of the machine or to -the steering wheel~
Means may also be provided to ensure the positive
drive of the wheels of the lower chassis, for example at the
low speeds of the machinel for travelling on the site. The
~- drive of the two pairs of wheels may then be rendered
selective or may be coupled~ The wheels provided on the super-
`~ structure are driving during high speed travel, particularly
on a highway.
The drive of at least one of the pairs of wheels may
also, if desired, be ensured directly by hydraulic wheel
motors.
,j:
It Will be readily understood that the invention thus
;~ 20 enables a machine to be produced which is capable of movingby its own means, both on the highway and on a site, when the
two pairs of wheels rest on the ground. The control of the
wheel-carrying arms enables the ground clearance to be ad~usted
and thus a lowering of the centre of gravity to be obtained
on the highway, thus providing a better stability, and a capa-
city of cl~aring obstacles on uneven ground, by increasing the
ground clearance. A diferential control of the wheel-carrying
arms of the lower chassis and the parallel connection of the
jacks of the wheel-carrying arms of the superstructure also
enable the machine to travel perpendicularly to the slope of
_ 5 _
;~
2Ll
the ground whilst remaining horizontal. The ste~ring of the
~ machine during its displacement is then ensured by ar-t;culation
; of its two parts about the axis of the gear ring~
For operation, the abutment of the stabilizers on the
ground in the desired position of orientation and the lifting
of the wheels of the superstructure provide for the rnachine a
good stability and allow the free rotation of the superstructure,
with its working attachment, through 360~ In -this conclition,
the differential control of the jacks of the wheel-carrying
arms and the stabilizer jacks enables the machine to be main-
tained in a horizontal position ? even on sloping land, this
facilitating work and making it possible to dig vertical tren-
ches in a direction perpendicular to the slope of the ground.
The invention will be more easily understood on reading
the following description with reference to the accompanying
drawings, in which -
Fig. 1 is a elevational view of the sel-propelled
hydraulic loading shovel according to the invention, in its
position for travel on -the highway.
Fig. 2 is a corresponding plan view.
Fig. 3 is a view similar to ~ig. 1, but showing the
shovel ready for operation~
Fig. 4 is a corresponding plan view~
Fig. 5 is a view similar to Fig. 3, showing the preferred
working position of the shovel~ in which the working attachment
is oriented towards the stabilizers.
Fig. 6 is a corresponding plan view.
Fig. 7 is an end view showing the machine in a position
enabling it to dig a vertical trench perpendicularly to the
direction of slope.
-- 6 --
. .
' '
6~2'~
Fig~ 8 and ~ are schematic representations o~ two
embodiments of propulsion 9 orienta-tion and steering systems
for the hydraulic shovel.
. ~ . .
`~ Referring now to the drawings, the self-propelled
hydraulic shovel shown therein comprises a lower chassls 1,
~` at one end of which are articulated arms 2 which may pivot
about a horizontal axis perpendicular to the longitudinal
~- direction of this lower chassis 1 and carrying front wh~els
` 3. ~rms 2 are controlled by means of jacks 4 also articulated
` 10 on this lower chassis 1.
,~ Stabilizers 5 are provided towards the other end of
this lower chassis 1~ on each of its sides. They are pivoted
~ about a horizontal axis 6 on a support 7 whichg itself, may
- pivot on the chassis 1 about a vertical axis. The stabilizers
5 are controlled ln the vertical plane by means of jacks 8
(Fig. 2).
Means (not shown) are provided on the lower chassis
for orientating the stabilizers 5 about the vertical pivotal
axis of the supports 7, between a position which in principle
is oriented at 90 with respect to the longitudinal axis of
the lower chassis 1 and ~arious positions of inclination on
this longitudinal axis 9 opposite the wheels 3~ The stabilizers
5 are provided with lower shoes 9 in a manner known per se.
~ superstructure generally designated by reference
numeral 10 is mounted on the lower chassis 1 so as to be able
to rotate through 360 via a gear ring 11 allowing orientation.
This superstructure carries, towards one end, a working
attachment which may be known per se and which is designed as
a whole by reference numeral 12, and at its other end a counter-
:
,`
3%~
~ .
weight 13. A cab 14, for the driver, i5 provided on the super-
structure laterally with respect to the working attachment 12.
Although a working atlachment has been shown here which
comprises a jib or boom assembled in two parts, an arm articu-
S lated on this jib or boom and a retro acting drag bucket, itwill be understood that this attachment may be arranged in any
desired manner and may also be interchangeable, without depar-
ting from the scope of the invention~
Opposite the working attachmen-t 12, the superstructure
10 carries, towards its lower part, wheel-carrying arms 15
hich may pivot on the superstructure 10 about horizontal axes
16 perpendicular to the normal longitudinal axis of the machine.
These arms 15 carry wheels 17 and their plvoting movement is
controlled by means of hydraulic jacks 18. In the embodiment
shown, the arms and jacks are articulated on the sides of the
superstructure 10. Driving systems of any type~ for example
chain and pinion drives, are in the present case housed inside
the arms 15 for the propulsion of the machine, the wheels 17
thus constituting driving wheels. However, it is obvious that
different propelling means, such as hydraulic wheel motors 7
might also be provided if desired~
The chambers of the jacks 18 associated with the wheels
17 are permanently in communication in two's, so that when an
outside action tends to displace one of the wheels 17 upwardly,
the other wheel moves by the same ampli-tude downwardly in a
compensating movement. This communication allows the four
wheels of the machine to remain in contact with the ground,
whatever the profile of the ground.
Fig,. 1 and 2 show the condition of the machine when it
- 8 -
; ~
'
.
:
`::
is travelling on a highway. It is seen that~ in this conditionl
-the arms 15 are lowered7 so that the machine rests on the ground,
at -the front tnrough the wheels 3 and at the rear through
wheels 17, the stabilizers 5 being lifted almost vertically on
S the sides. The drive o* the driving wheels 17 as indicated
hereinafter then ensures the propulsion of the machine. The
control of the arms 2 and 15 by means of the hydraulic jacks ~
and 18 enables the ground clearance of the machine to be adjusted
as desired, and in particular enables it to be given a small
; 10 clearance for its travel on a highway, this providing a good
stability. For tra~el on poor ground, tne ground clearance may
- be increased as desired by extending the jacks.
- In the condition of transport considered, it is under-
stood, as indicated in broken lines in Fig. 2, that it is
possible to pivot, by a certain angle with respect to one
another, the lower chassis 1 and the superstxucture 10 about
the gear ring 11, this enabling the machine to be directed due
to it5 articulated nature.
Figs. 3 and 4 show the prepara-tion of the machine for
` 20 operation. For this operation, the stabilizers 5 are folded
about horizontal axis 6 by means of the hydraulic jacks 8 and
they are pivoted by the supports 7 so as to take a suitable
orientation for the stability of the machine during the operation,
for example an orientation substantially at 45 with respect to
the longitudinal axis of the machine as shown in Fig. 4. Fig. 3
also shows that the arms 2 carrying the wheels 3 are controlled
so as subst:antially to reduce the ground clearance.
The wheel-carrying arms 15 are, moreover, lifted so that
-~ the wheels 17 are directed substantially upwardly, these wheels
, .
~ _ 9 ~
then being located 7 wi-th the arms, in the gauge of the super~
- structure 10.
When the position shown in F`igs. 3 and 4 ls obtained,
the orientation of the superstructure 10 is controlled so that
the working attachment is orienta-ted towards the stabilizers 5,
,,
this provicling an optimum stability during operation~ Opera-tion
may then take place normallyD To increase the depth of work, it
is also possible to control, by means of the jacks 4, the lif-ting
of arms 2 7 the machine then res-ting on the ground by its lower
chassis 1, the lateral s-tability always being ensured by the
stabilizers 5 7 of which the position in the vertical plane is
adjusked accordingly. A study of Fig. 5 shows that, in this
position, the wheels 3 indicated in broken lines occupy a
position corresponding to a clearance to the rear of the
lS superstructure 10, which therefore does not hinder the orienta-
tion thereof.
Fig. 7 shows the position occupied by the machine for
diggingl for example, a trench in a direction perpendicular to
the slope of the ground.
To carry out work of this type, the jacks 4 for adjusting
the arms 2 are subjected to a differential control, and the
same applies to the jacks 8 of the stabilizers 5, so as to
~ maintain the machine in the vertical position shown. The stabi-
- lity during operation is then very good and no tipping of the
machine is to be feared, the working attachment being able to
work vertically.
..
Moreover, it will be appreciated that this vertical
position o~ the machine may be obtained when said machine is
` travelling on sloping ground, by the suitable control of the
-:
-- 10 --
:.
6~
.
arms 2 carrying the wheels 3 and due to the comrnunication
. . .
` existing, as indicated hereinabove, between the jacks 16 asso-
.. ciated with the arms 15 carrying the wheels 17.
` Fig. 8 shows an embod:iment of the transmission systern
which may be used on the machine -forming the subject matter of
the invention, for ensuring :its propulsion, the control of
orientation of the superstructure 10 and the steering control
during travel of the machine.
The arrangement shown cornprises a main hydraulic motor
20 which is driven in any suitable manner from a pump provided
on the machine and whose outlet drives a first shaft 21 of a
gear or transmission box 22. This shaft 21 bears gear wheels 23
which mesh with gear wheels 24 mounted on a secondary shaft 25
; of the gear box 22, this shaft being associated with a sliding
gear 26 which allows the selective connection of one or the
other of the gear wheels 24 with shaft 25 9 to supply different
speeds at the outlet of the gear box 22~ This secondary shaft
25 constitutes the shaft for propelling the machine. It drives,
via a bevel gear 27, a differential 28 of conventional type
, ,
which, for its part, drives two half-shafts of wheels 29 ensu-
ring, through epicyclic trains 30 and a chain and pinion trans-
` mission 31 housed in the wheel-carrying arms 15, the drive of
the rear wheels 17 of the machinev Each half-shaft 29 carries
;~ a brake 32~
The secondary shaft 25 of the gear box 22 may drive,
through a ~og clutch system 33, another driven shaft 34 which,
itself~ ensures, through a bevel gear 35, the drive of a pinion
36 meshing with a gear ring 37 which constitu-tes the active
element of the gear ring 11 determining the orientation of the
.:
:
superstructure 10 of the machine. Thus, upon dog cl-u-tch enga~
gement of the device 33, -the main motor 20 ensures the orien-
-tation of the superstructure 10 of the machine in the desired
manner. The locking of the orientation may be ensured by the
brakes 32~
Fig. 8 also schematically shows a steering wheel 38
which is associated with a device 39 for hydraulically con-trol~
ling the steering, ensuring the control of a small hydraulic
~ .
pump 40 through a valve 4~. The driven shaft of this hydraulic
pump carries a pinion 42 which meshes with a gear wheel 43
carried by the shaEt 34.
When -the device 33 is disengaged and the valve 41 is in
a position of communication, a manoeuvring of the steering wheel
38 ensures, by the devic~ 39, the auxiliary motor 40 and the
gearing 42, 43, the drive of shaft 34, and, by said latter and
`~ the bevel gear 35, the drive of pinion 36 and consequently of
; the gear ring 37t to provide an angular displacement of small
amplitude of the superstructure 10 with respect to the lower
chassis 1, as shown in Fig. 2, this thus enabling the machin~
to be steered when running.
The valve 41 makes it possible, when it is brought into
out-off position, to avoid the drive of the sterring wheel
during the manoeuvres of orientation of the superstructure 10
. ~
from the main motor 20, as îndicated previously.
Fig. 9, in which elements similar to those shown in
Fig. 8 have been designated by the same references~ shows
another embodiment in which the orientation and steering during
running are both ensured from an auxiliary motor 44 of which
the driven shaft drives a gearing 45 which itself controls the
- 12 -
''~'
',~'
,'
. . . ~
. ~ .
~ i3~'~
bevel gear 46 drivin(3 the pinion 36 in mesh with the gear rinq
37. A valve 47 is here provided between the circuit comprising
the auxiliary motor 4~ and the steering sys-te~ 38, 39 and the
hydraulic supply of the mach-Lne~ in order to ensure, in one
position, through auxiliary walves 48, the direct supply of
the auxiliary motor 44, for the orientation of the superstruc-
ture 10, by isolating the steering wheel and7 in the other
position, the communication oF the device 39 with the auxiliary
motor 44, by isolating all -the hydraulic system of the machine,
for the steering control.
It is seen that an articulated self-propelled hydraulic
loading shovel is thus obtained which may -tra~el either with a
small clearance for transport on the highway or with a conside-
rable clearance or transport on uneven ground, by the control
o the hydraulic jacks 4 and 18 associated with the wheel-
carrying arms 2 and 15. The steering of this hydraulic shovel
is ensured by a relative displacement between the lower chassis
1 and the superstructure 10 by simple means, without steering
axle and in such a manner as to furnish a radius of turn of
reduced value, ensuring a good handling ability.
When the machine is travelling on a sloping ground in
a direction perpendicular to the slope, it may conserve a
horizontal position by suitable control of the jacks 4 of the
front wheels 3 and by the compensation between the jacks 18 of
the rear wheels 17. This position may be retained by the combi-
nation of the action of the stabilizers with that of the wheels,
this allowing a correction of considerable slopes, making it
possible to dig vertical trenches perpendicularly to the slope.
Finally, as indicated hereinbefore, the machine may rest on the
~ound via its lower chassis, -this increasing the depth of digging.
_ 13 -
. ' ~
